I see. What level of elite did you manage to hold by not flying NW much? I would have to guess you were "downgraded" because you did not fly whatever miles were needed for that status? Or are you saying they decided to stick it to you by denying a given elite level you were otherwise entitled to?
NW is not, from most posts here, especially generous with comps. For those that have achieved elite status by flying (a lot in some cases), that actually doesn't seem like such a bad idea.